Update library version to 2.19.0
diff --git a/ChangeLog b/ChangeLog
index 77d9d81..3d6ae07 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,6 +1,6 @@
 mbed TLS ChangeLog (Sorted per branch, date)
 
-= mbed TLS x.x.x branch released xxxx-xx-xx
+= mbed TLS 2.19.0 branch released xxxx-xx-xx
 
 Features
    * Add new API functions mbedtls_ssl_session_save() and